There are smart devices which include a graphics processing unit (GPU) which executes drawing process and a central processing unit (CPU) that issues a drawing command to GPU. Smart devices are also referred to as smart terminals. In such a smart terminal, in order to reduce power consumption, in GPU, while drawing process is not performed, clock gating in which input of a clock signal to GPU is stopped is performed. For example, related art is disclosed in International Publication Pamphlet No. WO 2008/126192, Japanese Laid-open Patent Publication No. 2008-271118, Japanese Laid-open Patent Publication No. 2007-41143, and Japanese Laid-open Patent Publication No. 2011-60193.